Animal stunning

ABSTRACT

Described are animal stunning apparatus and methods for inducing rapid unconsciousness and insensibility. The apparatus includes a stunning station in which a live subject animal is located in a confined position and an applicator contacts an application point on the live subject animal&#39;s head immediately overlying a frontal portion of the animal&#39;s brain and couples microwave radiation to the head. A microwave generator generates microwave energy of a suitable power level and frequency, and a waveguide directs the microwave radiation to the applicator. A switch discontinues the application of microwave radiation effecting heating of the frontal portion of the brain after a period of time sufficient to have raised the temperature of the frontal portion of the brain of the subject animal to thereby induce the unconsciousness and insensibility. The period is sufficient only to rapidly induce insensibility, and is insufficient for the insensibility induced to be irreversible, and insufficient to cause significant heating of deeper brain tissues and including the brain stem.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/668,030, filed Nov. 2, 2012, which will issue as U.S. Pat. No.8,506,366 on Aug. 13, 2013, which application is a continuation-in-partapplication of International Patent Application PCT/AU2011/000527, filedMay 9, 2011, designating the United States of America, and published inEnglish as WO 2011/137497A1 on Nov. 10, 2011, that claims priority fromAustralian Patent Application No. 2010901954 filed May 7, 2010, thecontents of the entirety of each of which are incorporated herein bythis reference.

TECHNICAL FIELD

This application relates to methods and apparatus for stunning ofanimals to induce unconsciousness and insensibility enabling processingor handling of the animal.

BACKGROUND

In slaughtering a live animal in an abattoir for production of meat,hide, and other by-products, the animal is usually restrained and thenstunned to induce immediate unconsciousness and insensibility. Theslaughter can then be performed without avoidable fear, anxiety, pain,suffering and distress. The stunning can also help avoid difficultiesand dangers for persons involved in the processing and handlingoperations. The “stunning” is commonly carried out either by anmechanical process, such as applying concussion by means of a projectilecaptive bolt (penetrating or non-penetrating mushroom headed knocker)impacted against the skull of the animal, or by electrical currentapplied to the animal and passed through the brain, or by inhalation ofgases such as carbon dioxide, nitrogen or argon.

The terms “stun” or “stunning” are frequently used to refer toirreversible processes, i.e., the “stunning” process causes irreversibledamage to the animal, particularly the brain. This may not be adifficult or contentious issue with regard to animal welfare concernsbecause the slaughter, such as by sticking and exsanguination,immediately follows the stunning and is therefore performed on anirreversibly unconscious and insensible animal.

However, with religious slaughter or ritual slaughter, irreversiblestunning is not acceptable. The animal must not be injured or harmedprior to exsanguination. For example, with the Muslim slaughter methodor “Halal slaughter,” the animal is required to be alive at the time ofslaughter. This requirement does not necessarily mean that the animal isnot permitted to be first stunned prior to slaughter, as long as thereis no injury, e.g., significant damage to the skull, but irreversiblestunning may well be unacceptable to comply with the dictated ritualrequirements. Likewise with the Jewish or Judaic slaughter method or“Shechita,” post-cut stunning of the animal may be permissible, but notirreversible pre-cut stunning that may be deemed unacceptable so thatthe resulting carcass would not be Kosher.

There have been some references in the published patent literature touse of microwave radiation stunning of animals for slaughter.

U.S. Pat. No. 3,973,290 refers to stunning an animal for slaughter byapplying microwave energy to penetrate the animal's skull and heat thebrain. A microwave beam is proposed to be directed at the animal withoutrestraining it, the energy being applied from the side of the skull.Such methods of application would create considerable surrounding tissuedamage by largely indiscriminate heating and therefore would be anirreversible process, causing harm to the animal, and is likely to beinhumane.

U.S. Pat. No. 4,616,160 describes a microwave heating apparatus forirradiating the entire head of test animals, particularly rodents. Theconfiguration of the apparatus including the manner of coupling themicrowave energy to the animal will heat the entire head of the animal.The specification does not explain whether the purpose is to stun theanimal but, if so, many organs and tissues of the head are likely to bedamaged and the apparatus would therefore be unacceptable from the pointof view of animal welfare.

DE 4116670 describes and illustrates an apparatus for irradiating a pigwith multiple microwave applicators arranged around the head and in arow along the length of the spine, all being spaced from the animal. Useof such an apparatus design will irreversibly damage tissues by cookingaffected tissues, which is likely to be inhumane.

JP 3039615 describes apparatus for slaughtering animals using microwavesto heat the brain causing cerebral death.

SUMMARY OF THE DISCLOSURE

Provided are processes and apparatus for stunning of animals to inducerapid unconsciousness and insensibility. Particularly provided areprocesses and apparatus for stunning of animals to induce rapidunconsciousness and insensibility in a manner that the stun isreversible, meaning that the animal can later regain consciousness andsensibility without significant loss of brain mediated functionincluding motor functions, sensory processing, innate and instinctivefunctioning, learned behavior, etc.

With such reversible animal stunning processes and apparatus, animalsfor slaughter can be stunned in a manner to enable subsequent processingand handling, including slaughter, whilst the system still remainscompliant with certain religious slaughter rituals. The achievement ofreversible stunning processes and apparatus may also enable suchstunning of animals for other kinds of processing or handling, such asfor veterinary inspections or purposes, banding, branding, tagging,inspection recording and re-release, etc. However, the particularprocesses and apparatus described herein will refer to the primaryintended field of application, namely slaughtering of animals for foodproduction, hide recovery and treatment, and other by-product extractionand processing.

In one aspect, provided is an animal stunning apparatus for inducingsubstantially immediate unconsciousness and insensibility enablingprocessing or handling of a subject animal, the apparatus including:

-   -   a stunning station to which a live subject animal to be        processed or handled is introduced, the stunning station being        arranged to locate the subject animal in a confined position,    -   an applicator located so as to contact an application point on        the live subject animal's head immediately overlying a frontal        portion of the animal's brain, the applicator having a coupling        conformation to couple microwave radiation therethrough to the        head and to the frontal portion of the brain of the subject        animal when in the confined position at the stunning station,    -   a microwave generator for generating and radiating microwave        energy of a suitable power level and frequency, and a waveguide        coupled to the generator so as to receive and direct the        microwave radiation to the applicator located at an operative        end of the waveguide so as to thereby heat the frontal portion        of the brain of the subject animal beneath the application point        which the applicator contacts in use, and    -   a switch operable so as to discontinue the application of        microwave radiation effecting heating of the frontal portion of        the brain after a period of time sufficient to have raised the        temperature of the frontal portion of the brain of the subject        animal to thereby induce the unconsciousness and insensibility,        wherein the switch is operable to discontinue the application of        microwave radiation immediately after a period which is        -   sufficient only to rapidly induce insensibility, and        -   insufficient            -   (i) for the insensibility induced to be irreversible,                and            -   (ii) to cause significant heating of deeper brain                tissues and including the brain stem.

Preferably, the application point is medially located on the head of thesubject animal above a line extending between the animal's eyes so as tobe located at the closest external point to the central and frontalportion of the brain.

An applicator may have an opening therein through which the microwaveradiation from the waveguide is coupled to the animal's head at theapplication point, the peripheral portions of the applicator definingthe opening contacting the animal's head to surround the applicationpoint when the applicator is in its operative position. The opening ofthe applicator preferably has an area chosen to provide impedancematching between the impedance of the applicator and the tissues at theapplication point, the area being bounded by the peripheral portions ofthe applicator which is composed of shielding material to provide powertransfer to the animal tissues without microwave leakage. The peripheralportions of the applicator may be composed of shielding material and areconfigured to press into the surface tissues of the animal, typically byabout 1-2 mm, to promote good coupling and microwave energy transferwithout leakage and to resist transverse movement of the applicator ifthe animal attempts to move its head. By applying the peripheralportions of the applicator defining the opening so that they contact theanimal's head surrounding the application point, good coupling of themicrowave power from the waveguide through the applicator to theanimal's head can be achieved and leakage and loss of microwave energyto the surroundings can be minimal, preventing tissue damage, andtherefore more humane stunning may be achieved.

The applicator may have a coupling disk composed of microwave permeablematerial at the opening, the coupling disk being pressed positivelyagainst the animal head at the application point to provide an interfacefor transferring power at the application point. The coupling disk maybe composed of a ceramic material to provide a robust interface for highpower transfer. A further ceramic disk may be located in the microwavepath of the applicator, the further disk being located upstream of thecoupling disk a distance of ¼ of the wavelength of the microwaveradiation so as to counteract negative affects of the ceramic couplingdisk.

In one embodiment, the applicator comprises a coaxial applicator passingmicrowave radiation from the operative end of the waveguide to theapplication point, the coaxial applicator having a central conductorthrough the length of the applicator, the central conductor beingcoaxially located within a surrounding conductive sleeve therebydefining an annular microwave path from the waveguide to the couplingconformation. The coaxial applicator may include a conical section toconcentrate the microwave energy from the waveguide upstream, theconical section having a gradual transition to the desiredcross-sectional area of the coupling conformation while maintainingacceptable power transfer therethrough. The microwave path through thecoaxial applicator may be filled with a dielectric material so as toenable higher powered densities than air and to modify or tune theimpedance.

The coaxial applicator may be connected to the operative end of thewaveguide so as to extend therefrom at an angle to the general line ofthe waveguide, the connection between the operative end of the waveguideand the coaxial applicator being provided by a transition structureincluding a tapering cross-section area to provide a gradual change inimpedance from the waveguide and to provide matching of the impedancebetween the waveguide and the coaxial applicator and to limit or reducereflected power losses.

The applicator may be constructed and arranged to apply the microwavesto the animal's head so that the electric field of the microwave energyenters the subject animal's head generally perpendicularly to penetratethe skin and skull at the application point and induce rapid heating ofthe frontal portion of the animal's brain.

In one embodiment, the generator is a TE type wave generator and theapparatus further includes a mode transformer operative to convert theTE type wave to a TM wave. Alternatively for greater power density thegenerated microwave radiation may comprise a TEM type wave whereby boththe electric and magnetic fields enter the subject animal's headgenerally parallel to the skin surface at the application point.

To increase the rate of heating of the animal head and particularly ofthe frontal brain region, and thus decrease the duration of the heatingtime necessary to induce unconsciousness and insensibility, theapparatus preferably further includes an auto-tuner operativelyassociated with the waveguide and which detects the reflected power ofmicrowave radiation in the waveguide resulting from the degree of theimpedance matching between the applicator and the head and which tunesthe waveguide to reduce the reflected power and increase the coupling ofthe microwave power to the head. The auto-tuner may be operated in aniterative manner to continually tune the waveguide during theapplication of microwave radiation so as to continually improveimpedance matching while the impedance of the head changes due toheating.

In one embodiment, the apparatus further includes applicator movingmeans operative to selectively advance the applicator from a retractedposition where it is located when the subject animal is being located inthe confined position at the stunning station to an operative positionwhen the animal is located and held in its confined position, theapplicator in its operative position being engaged against the animal'shead at the application point, the direction of the microwave radiationthrough the waveguide to the applicator being carried out only after theapplicator is in its operative position. The applicator moving means maybe operative to telescopically move the applicator from its inoperativeposition to its operative position contacting the animal head. A guidingsystem may be associated with the movable applicator for guidingmovement of the applicator from its inoperative to its operativeposition, the guiding system including sensor means to sense thepresence and location of the animal's head and to which the guidingsystem is responsive.

In another embodiment, the stunning station includes a head positionerto locate and present the subject animal's head in a defined position tothe applicator. The head positioner may include a head lifter means tolocate and lift the subject animal's head to the applicator which is ina predetermined position for the presentation of the animal's headthereto. This may comprise a head “tilter” to lift the animal's head bytilting it upwardly to present the application point to the applicator.The head tilter may comprise a chin lifting member to lift the chin orlower jaw of the animal upwardly and tilt the head backwardly to presentthe application to the applicator.

In this embodiment, the head positioner may further include a head tiltlimiter towards which and into contact with which the head lift meanstilts the animal head, the tilt limiter typically comprising a fixedabutment contacted by the top back portion of a animal's head when thehead has been lifted and tilted sufficiently to present the applicationpoint to the applicator. Furthermore the head positioner may include aneck lifter selectively operable to raise the animal's head (withoutnecessarily tilting of the head) by lifting force applied from beneathto the neck of the animal, thereby raising the head towards theapplicator particularly enabling different height animals to beprocessed.

In one possible apparatus, the head positioner includes a body lifterselectively operable to raise the animal's body (without necessarilyseparately lifting or tilting of the head or lifting the neck) bylifting force applied from beneath to the body of the animal, therebyraising the head towards the applicator particularly enabling differentheight animals to be processed. In a further possible apparatus, thestunning station includes a body support for the animal support theanimal during the application of the microwave energy in case the animalslumps or falls at the onset of insensibility.

Preferably the stunning station includes microwave shielding surroundingat least the position of the animal head when the animal is confinedthereby forming a Faraday cage, the shielding having an opening in whichthe animal's head is located.

Also provided is a method of stunning an animal for inducingsubstantially immediate unconsciousness and insensibility enablingprocessing or handling of the animal, the method including the steps of:

-   -   introducing a live subject animal to be processed or handled to        a stunning station and locating the animal in a generally        confined position,    -   locating an applicator in contact with an application point on        the animal's head immediately overlying the frontal portion of        the subject animal's brain, the applicator having a coupling        conformation to couple microwave radiation through the        applicator to the head and to the frontal portion of the brain        of the subject animal,    -   generating microwave radiation of a suitable power level and        frequency and directing that radiation through a waveguide to        the applicator at an operative end of the waveguide to thereby        heat the frontal portion of the brain of the subject animal,        -   wherein the application of the microwave radiation to effect            the heating is continued for a period of time to raise the            temperature of the frontal portion of the brain, the period            being sufficient only to rapidly induce insensibility, and        -   insufficient            -   (i) for the insensibility induced to be irreversible,                and            -   (ii) to cause significant heating of deeper brain                tissues and including the brain stem.

In one possible embodiment, the microwave radiation generated has itselectric field generally perpendicular to the front of the animal's headat the application point whereby the electric field enters the animal'shead in a generally perpendicular direction. In an alternative possibleembodiment, the microwave radiation generated has both its electricfield and magnetic field generally parallel to the front of the animal'shead at the application point and whereby the microwave radiation entersthe animal head in the generally perpendicular direction.

Preferably, the frontal portion of the brain of the subject animal isheated so as to increase the temperature by an amount in the range ofabout 5° C. to about 10° C., and most preferably the frontal portion ofthe brain of the subject animal is heated to a temperature of about 43°C.

Also provided is a method of handling and processing an animal, themethod including the steps of:

-   -   stunning the animal to rapidly induce unconsciousness and        insensibility enabling processing or handling of the animal, the        stunning step including:    -   introducing a live subject animal to be handled and processed to        a stunning station and locating the animal in a generally        confined position,    -   locating an applicator in contact with an application point on        the animal's head immediately overlying the frontal portion of        the subject animal's brain, the applicator having a coupling        conformation to couple microwave radiation through the        applicator to the head and to the frontal portion of the brain        of the subject animal,    -   generating microwave radiation of a suitable power level and        frequency and directing that radiation through a waveguide to        the applicator at an operative end of the waveguide to thereby        heat the frontal portion of the brain of the subject animal,    -   wherein the application of the microwave radiation to effect the        heating is continued for a period of time to raise the        temperature of the frontal portion of the brain, the period        being        -   sufficient only to rapidly induce insensibility, and        -   insufficient            -   (i) for the insensibility induced to be irreversible,                and            -   (ii) to cause significant heating of deeper brain                tissues and including the brain stem;    -   performing on the animal in the unconscious and insensible state        a process selected from general purpose inspection, general        purpose treatment, veterinary inspection, veterinary treatment,        docking, tagging, and branding; and    -   subsequent to the step of performing the selected process,        reviving the animal by returning the temperature of the frontal        part of the brain towards its normal operating temperature so        that the animal regains consciousness and sensibility without        significant loss of brain mediated function.

Also provided is a method of stunning and subsequently slaughtering ananimal, the method including the steps of:

-   -   stunning the animal for rapidly inducing unconsciousness and        insensibility, the stunning step including:        -   introducing a live subject animal to be slaughtered to a            stunning station and locating the animal in a generally            confined position,        -   locating an applicator in contact with an application point            on the animal's head immediately overlying the frontal            portion of the subject animal's brain, the applicator having            a coupling conformation to couple microwave radiation            through the applicator to the head and to the frontal            portion of the brain of the subject animal,        -   generating microwave radiation of a suitable power level and            frequency and directing that radiation through a waveguide            to the applicator at an operative end of the waveguide to            thereby heat the frontal portion of the brain of the subject            animal,        -   wherein the application of the microwave radiation to effect            the heating is continued for a period of time to raise the            temperature of the frontal portion of the brain, the period            being            -   sufficient only to rapidly induce insensibility, and            -   insufficient                -   (i) for the insensibility induced to be                    irreversible, and                -   (ii) to cause significant heating of deeper brain                    tissues and including the brain stem; and        -   while the animal is in the unconscious and insensible state,            slaughtering the animal in a manner compliant with religious            ritual slaughter criteria prescribed for Muslim “Halal”            slaughter or for Judaic “Shechita” slaughter.

Also provided is an animal stunning apparatus for rapidly inducingunconsciousness and insensibility enabling processing or handling of asubject animal, the apparatus including:

-   -   a stunning station to which a live subject animal to be        processed or handled is introduced, the stunning station being        arranged to locate the subject animal in a confined position,        the stunning station including head positioning means to locate        and present the subject animal's head in a defined position;    -   an applicator located relative to the subject animal's head when        in its defined position so as to contact an application point on        the live subject animal's head immediately overlying a frontal        portion of the animal's brain, the application point being        medially located on the head of the subject animal above a line        extending between the animal's eyes so as to be located at the        closest external point to the central and frontal portion of the        brain, the applicator having a coupling conformation to couple        microwave radiation therethrough to the head and to the frontal        portion of the brain of the subject animal when in the confined        position at the stunning station, the applicator having an        opening therein through which the microwave radiation from the        waveguide is coupled to the animal's head at the application        point, the peripheral portions of the applicator defining the        opening contacting the animal's head to surround the application        point when the applicator is in its operative position;    -   a microwave generator for generating and radiating microwave        energy of a suitable power level and frequency, and a waveguide        coupled to the generator so as to receive and direct the        microwave radiation to the applicator located at an operative        end of the waveguide so as to thereby heat the frontal portion        of the brain of the subject animal beneath the application point        which the applicator contacts in use, stunning station including        microwave shielding surrounding at least the position of the        animal head when the animal is in its confined position thereby        forming a Faraday cage, the shielding having an opening in which        the animal's head is located; and    -   switching means operable so as to discontinue the application of        microwave radiation effecting heating of the frontal portion of        the brain after a period of time sufficient to have raised the        temperature of the frontal portion of the brain of the subject        animal to thereby induce the unconsciousness and insensibility.

BRIEF DESCRIPTION OF THE DRAWINGS

Possible and preferred features of the invention will now be describedwith particular reference to the accompanying drawings. However it is tobe understood that the features illustrated in and described withreference to the drawings are not to be construed as limiting on thescope of the invention. In the drawings:

FIG. 1 is an illustration of a cattle head with the application pointfor the microwave radiation indicated.

FIG. 2 schematically illustrates in side view an animal stunning stationwith stunning apparatus according to one embodiment of the invention.

FIG. 3 is a perspective view of parts of an animal stunning station anda possible head positioning means.

FIG. 4 is a cross-sectional view of a terminal end portion of thewaveguide leading to the applicator.

FIGS. 5 and 6 are schematic side views of an alternative configurationof applicator shown in its retracted inoperative and advanced operativepositions respectively.

DETAILED DESCRIPTION

The illustrated apparatus of FIGS. 2 and 3 includes an animal stunningstation 10 which includes an enclosure 11 or crush, such as a knockingbox of an abattoir. Although the drawings and associated descriptionrelate to a fixed position of stunning station, it is to understood thatthe stunning station can be itself moving, e.g., along a conveyor, andthe expression in the specification and claims includes such a movingstunning station. The animal is introduced into the enclosure throughentrance 12 and confined therein between the entrance 12, which has adoor which closes behind the animal, side walls 14,15 and head end 17.Side wall 15 is shown closed in FIG. 2 but can be selectively raised asshown in FIG. 3 to enable side discharge of the carcass after stunning.The floor 18 is shown slightly sloping to the side to promote thesideways discharge. A pusher 16, initially retracted when the animalenters the enclosure 11 through the entrance 12, can be located behindthe animal and then moved towards the head end 17 so as to urge theanimal to present its head as required. An opening 20 at the head end 17of the enclosure 11 enables the animal to place its head 50 through theopening which it will naturally do to look for an exit and which, in anautomated system, can be encouraged the pusher 16 or by conveying theanimal on a moving floor or conveyor system 18 into the knocking box.The opening 20 is initially substantially larger than shown in FIGS. 2and 3 by providing vertically movable upper and lower panels 21, 22which are relatively moved apart to enable the animal to insert its headthrough the opening 20 defined by the shaped lower and upper edges ofthe panels 21, 22 respectively. When the head 50 has passed through theopening 20, the panels 21, 22 are immediately moved to confine the neckof the animal and prevent it retracting its head 50 back through theopening 20. If desired laterally movable head or neck bails, e.g.,closely adjacent to and either inside or outside of the head end wall 17(known in the art) can laterally confine the head and/or neck.

In the embodiment of FIGS. 2 and 3, the stunning station 10 includeshead positioning means 25 to locate and present the animal's head 50 ina defined position to the microwave applicator 60. The head positioningmeans 25 includes a head lifter means 26 to locate and lift the head 50to the applicator 60 which is in a predetermined position for thepresentation of the head 50 thereto. The head positioning means isillustrated as a head tilting mechanism to lift the animal's head 50 asshown at 50 a in FIG. 2. The applicator point 51 where the microwaveradiation is to be applied by the applicator 60 is, as shown in FIG. 1,medially located on the head above a line extending between the animal'seyes so as to be located at the external point closest to the centralfrontal portion of the brain. In the case of cattle, the applicationpoint 51 can be located substantially medially at the recommended pointwhere percussion is applied in the present known mechanical stunningprocesses, whether using a captive bolt stunning apparatus or using anon-penetrating impacting tool. As shown in FIG. 2, when the head islifted by tilting to the position 50 a, the application point 51 ispresented to the applicator 60.

The head tilting means 26 comprises a chin lifting member shown as aframe or cradle 27 which generally conforms to the shape of the jaw andwhich is operated to lift the chin or lower jaw of the animal upwardlyand tilt the head 50 backwardly to present the application point 51 tothe applicator 60. The chin lifting frame or cradle 27 may includerestraints mounted at each side and shaped and positioned to locatebehind the cheek bones and further inhibit or prevent the animal pullingits head 50 backwardly once it has been engaged and is being positioned.The lifting of the animal's head 50 is by pneumatic ram 28 which pivotsthe frame or cradle 27 upwardly about pivot axis 29 (schematically shownin FIG. 2 in front of the end 17, but behind end 17 in FIG. 3).

The head positioning means 25 further includes a head tilt limiter 30towards which and into contact with which the head lift means 26 tiltsthe animal head 50. The tilt limiter 30 is shown as a fixed abutment 31contacted by the top back portion 52 or “poll” of the animal's head 50when the head has been lifted and tilted sufficiently to present theapplication point 51 to the applicator 60. The tilt limiter 30 can bedifferently shaped, sized, and positioned and can if desired beselectively movable to accommodate different sizes and breeds of animaletc. so that the application point 51 is reliably and accuratelypresented to the applicator 60.

In the embodiment of FIG. 3, the selectively vertically movable lowerpanel 22 of the head end wall 17 constitutes a neck lifting means 35because it is operable to raise the animal's head 50 by lifting forceapplied from beneath the neck of the animal thereby raising the head 50towards the applicator 60 and enabling for example different heightanimals to be processed.

The head positioning means 25 may also include a body lifting meansselectively operable to raise the animal's body (without necessarilyseparately lifting or tilting of the head or lifting of the neck) bylifting force applied from beneath the body of the animal, therebyraising the head 50 towards the applicator 60 particularly to enabledifferent height animals to be processed. For example, the body liftingmeans may comprise means to selectively raise and lower the floor 18 ofthe enclosure 11. Alternatively, the entire enclosure 11 may be raisedto present the animal head 50 to applicator 60.

In a further possibility, the stunning station 10 may include a bodysupport for the animal operative to support the animal during theapplication of the microwave energy in the event that the animal startsto slump or fall at the onset of insensibility. For example, the walls14, 15 may be relatively selectively movable towards each other to actas a crush which closely confines and supports the animal body. E.g.,the wall or walls 14, 15 may slope inwardly towards their bottom edges.Alternatively, or in addition, a selectively retractable support may beinserted to fit beneath the brisket and provide support for the thoraxif the animal starts to fall or slump after the application of microwaveenergy commences but before the end of the energy application period.

The stunning station in the illustrated apparatus of FIGS. 2 to 4locates the animal in the confined position so that the applicator 60can contact the application point 51 immediately overlying a frontalportion of the animal's brain. The applicator 60 has a couplingconformation 61 to couple microwave radiation therethrough to the head50 and of the animal. A microwave generator 75 generates and radiatesmicrowave energy of a suitable power level and frequency. Waveguide 76is coupled to the generator so as to receive and direct the microwaveradiation to the applicator 60 located at an operative end 77 of thewaveguide. Switching means 78 is operable so as to discontinue theapplication of microwave radiation effecting the heating of the frontalportion of the brain after a period of time sufficient to raise thetemperature of the frontal portion of the brain of the animal to therebyinduce unconsciousness and insensibility.

If the animal is to be stunned for ritual slaughter requiring the animalto be live, the switching means 78 is operable to discontinue theapplication of microwave radiation immediately after a period which is:

-   -   sufficient only to rapidly induce insensibility and    -   insufficient        -   (i) for the insensibility induced to be irreversible, and        -   (ii) to cause significant heating of the brain tissues and            including the brain stem.

Such timing of the application of radiation may also be applicable ifthe animal is to be held insensible for a time, e.g., for performingveterinary tests or processes, after which the animal is to be returnedto its normal sensible and conscious condition by allowing thetemperature of the front portion of the brain to return to normal. Inthis situation, if the animal is to be held insensible for a period oftime, the application of microwave radiation may be pulsed orintermittent so as to maintain the insensible state.

FIG. 2 schematically illustrates the waveguide 76 provided with anassociated auto-tuner 90 so as to improve the tuning efficiency andeffectiveness between different animals being processed and to enableadjustment of the tuning as the dielectric properties of the animalheads change with temperature. As each animal head has a slightlydifferent impedance, tuning of the impedance of the waveguide andapplicator to each animal head as it is presented is beneficial.

The auto-tuner 90 in FIG. 2 includes a directional coupler 91 mounted toand operatively associated with the waveguide 76. For example thecoupler samples the standing wave in the waveguide, e.g., by providingprobes 92 at spaced points lengthwise of the waveguide, optimally at 60°intervals of the guide wavelength. The coupler 91 provides data signalsto the processor 94 which can be a PC programmed to analyze the signalsfrom the coupler 91 and to determine forward and reflected power levels.A target reflected power level may be programmed for the apparatus toachieve by tuning of the waveguide. Effectively the coupler 91 andassociated processor 94 are determining the impedance by determining thereflection co-efficient of the microwave load (i.e., the head 50.

The apparatus also includes a tuner 96 associated with the waveguide 76and which is responsive to the processor 94. The tuner may for examplecomprise moveable members 97 having associated drives 98 so that, inresponse to command signals from the processor 94, the drives 98 movethe respective positions of the members 97 within the waveguide 76,thereby altering the impedance characteristics. The direction and extentof the movements of the members 97 are controlled by the processor so asto adjust the reflected power towards the programmed target and therebyimprove the coupling of the microwaves to the head 50.

Each animal head 50 has a slightly different impedance, e.g., due todifferences in the sizes and composition of the heads, and due to thepositions of the heads in relation to the applicator 60. As soon aspower is applied, the auto-tuner 90 begins analyzing the impedance andadjusting the tuner 96 so as to improve the impedance matching betweenthe waveguide 76 and applicator 60 and head 50. As the application ofmicrowave radiation to the head 50 occurs and warming of the head andfrontal brain tissues begins, the impedance of the head 50 will change.Therefore the auto-tuner 90 is operative to continually monitor thereflected power and to automatically adjust the tuner 96 and maintain orimprove the power coupling to the head 50. Thus by automaticallyimpedance matching between the waveguide and applicator and the head atthe commencement of the stunning operation, and by continuallymonitoring and auto-tuning of the waveguide in an iterative manner tomaintain impedance matching, the rate of heating of the animal head 50and particularly of the frontal brain region can be increase, thusdecreasing the duration of the heating time necessary to induceunconsciousness and insensibility.

Auto-tuners suitable for use in the apparatus of the invention may becomposed of a “Homer Analyzer” (an automatic impedance and powermeasurement system) from S-TEAM Lab, Slovak Republic, which isoperatively coupled to a motorized tuner such as one obtained from, oranalogous to those made by, Muegge GmbH (Reichelsheim, Germany).

Referring particularly to FIG. 4, the applicator 60 has an opening 62through which the microwave radiation from the waveguide 76 is coupledto the animal's head 50 at the application point 51. The peripheralportions 63 of the applicator defining the opening 62 contact theanimal's head so as to surround the application point 51 when theapplicator 60 is in its operative position. The area of the opening 62is chosen to provide impedance matching between the impedance of theapplicator 60 and the tissues at the application point 51. The areabounded by the peripheral portions 63 are composed of shieldingmaterial, typically metal, to provide power transfer to the animaltissues without microwave leakage. As shown in FIG. 4, the peripheralportions 63 composed of shielding material are configured so as toproject slightly beyond the opening 62 so that they press into thesurface tissues of the animal, typically by about 1-2 mm, to promotegood coupling and microwave energy transfer without leakage and also toresist transverse movement of the applicator 60 if the animal attemptsto move its head particularly generally in the plane of the opening 62.

The applicator 60 shown in FIG. 4 comprises a co-axial applicatorpassing microwave radiation from the operative end 77 of the waveguide76 to the application point 51. The co-axial applicator has a centralconductor 65 through the length of the applicator and which isco-axially located within a surrounding conductive sleeve 66 and therebydefining an annular microwave path 70 from the wave guide 76 to thecoupling conformation 61. The co-axial applicator includes a conicalsection 68 of the sleeve 66 to concentrate the microwave energy from thewaveguide upstream, the conical section 68 has a gradual transition tothe desired cross-sectional area of the coupling conformation 61 whilemaintaining acceptable power transfer therethrough. The microwave path70 through the co-axial applicator is filled with a dielectric materialso as to enable higher powered densities and to modify or tune theimpedance. A suitable dielectric material may be PTFE or polyethylenethat has a small loss tangent, i.e., much less than 1.0, to enable theuse of smaller dimensions of the applicator.

The co-axial applicator 60 in FIG. 4 is connected to the operative end77 of the waveguide 76 so as to extend therefrom at an angle (shown as90°) to the general line of the waveguide 76. The connection between theoperative end of the waveguide 77 and the co-axial applicator 60 isprovided by a transition structure 71 which includes a taperingcross-section area formed by the taper or ramp 72 to provide a gradualchange in impedance from the waveguide 76 and to provide matching of theimpedance between the waveguide 76 and the co-axial applicator 60 andlimit or reduce reflected power losses. The taper 72 and ridge 73function as part of the waveguide to co-axial applicator transition andprovide a way of matching the waveguide impedance with the co-axialapplicator impedance. The dimensions of the taper 72 and of thetransition structure 71 are determined based on the required impedanceof the co-axial applicator 60.

The centerline of the central conductor 65 and therefore of the co-axialapplicator 60 is located for maximum power coupling from the waveguideto the applicator. This is typically where the distance from the shortcircuit waveguide back wall to the centerline is one quarter or threequarter the wavelength. The dimensions of the central conductor 65remain constant in cross-section and that dimension is selected with theentire dimensions of the co-axial applicator 60 in mind. The internaland external conductor dimensions are chosen based on the desiredimpedance of the co-axial applicator 60 and its ability to handle highpower without voltage breakdown. The dimensions of the final section ofthe co-axial applicator provided by the sleeve portion 69 leading to theopening 62 are designed and dimensioned to match with the impedance ofthe animal's skin thus ensuring maximum power transfer. Anotherconsideration is to reduce the cross-sectional area of the opening 62 toas small as practical so that high power density can be delivered.

The applicator 60 in FIG. 4 has the coupling disc 80 composed ofmicrowave permeable material at the opening 62. The coupling disc 80 ispressed positively against the animal head at the application point 51to provide an interface for transferring power. The coupling disc 80 canbe composed of a ceramic material to provide a robust interface for highpower transfer. A further ceramic disc 81 is provided in the microwavepath of the applicator 60, the further disc 81 being upstream of thecoupling disc 80, preferably a distance of one quarter of the wavelengthof the microwave radiation, so as to counteract negative effects of theceramic coupling disc 80.

As shown in FIG. 2, the stunning station 10 includes a microwaveshielding surrounding at least the position of the animal head 50 whenthe animal is in its confined position. The shielding 80 forms a Faradaycage for limiting or preventing leakage of microwave radiation. Theanimal's head 50 in use extends through the opening 20 which constitutesan opening into the Faraday cage. The head end 17, particularly thepanels 21, 22 effectively form part of the Faraday cage.

In the alternative possible construction of applicator 60 shown in FIGS.5 and 6, there is provided applicator moving means 85 operative toselectively advance the applicator 60 from a retracted position shown inFIG. 5 where it is located when the animal is being located in theconfined position at the stunning station 10 to an operative positionshown in FIG. 6 when the animal is located and held in its confinedposition. The applicator 60 in its operative position in FIG. 6 engagesagainst the animal's head 50 at the application point 51 and the passingof the microwave radiation through the waveguide 76 to the applicatorbeing carried out only after the applicator 60 is in its operativeposition. As shown in FIGS. 5 and 6, the applicator moving means 85 isoperative to telescopically move the applicator 60 from its inoperativeposition to its operative position contacting the animal's head.

The apparatus may include a guiding system (not shown) associated withthe movable applicator 60 for guiding movement of the applicator fromits inoperative to its operative position, the guiding system includingsensor means such as micro switches, proximity sensors, head imagecapture means and head shape recognition software, etc., to sense anddetermine the presence and location of the animal's head and to whichthe guiding system is responsive to accurately place the opening 62 ofthe applicator 60.

In the arrangement in FIGS. 2 to 4, the radiation forms an angle ofincidence with the animal head at the application point 51 of about 90°,i.e., generally orthogonal to the flat portion of the animal skull abovethe line joining the eyes and immediately over the frontal portion ofthe brain. The generated microwave radiation preferably comprises a TEM(transverse electromagnetic) type wave whereby both the electric andmagnetic fields enter the animal head 50 generally parallel to the skinsurface. The use of TEM type waves enables higher power transfer throughthe animal tissues for fast heating.

In an alternative possibility, the microwave radiation generated has itselectric field generally perpendicular to the front of the animal's head50 at the application point 51 whereby the electric field enters theanimal's head in a generally perpendicular direction. Known apparatusfor microwave heating, such as in industrial processes in whichmicrowaves are used to heat food for cooking purposes, utilize microwaveradiation generated in a “transverse electric” or “TE” mode, meaningthat the propagating field has the electric field transverse to thedirection of propagation along the waveguide. However, the presentapparatus may convert a TE type wave to a “transverse magnetic” or “TM”wave in which the electric field is parallel to the propagationdirection so as to enter the animal's head at the application pointgenerally perpendicular to the surface of the animal's head at thatpoint. TM waves have a lower wave impedance than TE waves: Z=E/H, sothat a TM wave will have a lower electric field strength for aparticular power setting but it is the electric field strength than cancause arcing and skin heating favoring a TM wave. Also, it is believedthat thin material, such as skin, couples energy better when theelectric field is parallel to the surface of the material so that, inthe present preferred apparatus, our aim is to achieve the opposite,namely weaken the coupling of energy at the surface skin or hide layer.In this possible embodiment, therefore, risk of discomfort or pain tothe animal may be reduced by the application of the TM type microwaveenergy at the application point. Preferably where the generator is a TEtype wave generator, the apparatus further includes a mode transformeroperative to convert the TE type wave to a TM wave. The mode transformermay be located in series between the waveguide feed from the generatorand the applicator.

In this possible embodiment, the applicator has a conformation to applythe TM wave to the animal's head so that the electric field of themicrowave energy enters the subject animal's head generallyperpendicularly to penetrate the skin and skull at the application pointto induce heating of the frontal portion of the animal's brain.

The apparatus may also include an automatic timer control (not shown) tostart and terminate the application of microwave radiation to the animalhead depending on programmed criteria. For example, the knocking box mayinclude an animal weight sensor, the output of which is fed to the timercontrol which determines the necessary period for the application ofmicrowave radiation according to an algorithm or formula.

The microwave generator may be generally conventional in constructionand operation. The frequency of the microwave radiation generated andtransmitted through the associated waveguide may be any suitable value.Tests involving the application of microwave radiation to cattle andsheep heads have utilized microwave generators operating at frequenciescommercially utilized in Australia, namely 922 MHz and 2.45 GHz. Thesetests demonstrated that with the lower frequency 922 MHz there is betterpenetration of the energy and less unwanted heating of tissues at thesurface and in surrounding tissues, so such a lower frequency ispreferred. However, the optimum frequency or frequency range can bedetermined empirically and is believed to be in the range 500 MHz-1 GHz.

The power requirements of the microwave generator will be dependent onmany factors including, for example,

-   -   the type of animal to be stunned including species (sheep,        cattle, pigs, etc.)    -   the breed of the particular animal species (Hereford, Brahman,        etc.)    -   the age, body mass, and sex of the animal    -   the speed required to achieve effective stunning to induce        unconsciousness and insensibility,    -   the temperature rise required within the frontal portion of the        animal's brain necessary to induce the unconsciousness and        insensibility    -   whether TE mode, TM mode or TEM mode microwave radiation is        being generated and applied to achieve the frontal brain        heating.

Such factors are not necessarily entirely independent of each other.

For example, tests on sheep and cattle heads have produced dataindicative of the power requirements being:

-   -   for sheep, to induce a 10° C. temperature rise of the frontal        portion of the brain, in about one second: 40 kW power output.    -   for cattle (about 300 kg body weight), 10° C. temperature rise        of the frontal portion of the brain, within 1.5 seconds: 100 kW        power output.

These findings are indicative only because, as explained above, thereare many parameters affecting the power requirement to achieve a certainlevel of heating within a target time period commencing with switchingon of the microwave radiation. Therefore, the power requirements for thegenerator can be empirically determined.

Preferably the temperature rise of the frontal portion of the brain toinduce reversible unconsciousness and insensibility is in the range ofabout 5° C. to less than about 10° C. For example, tests with live(anesthetized) sheep showed frontal brain heating to about 43° C.produced electroencephalogram (EEG) traces similar to those observedwith electric stunning now widely used in abattoirs, thus indicatingthat that temperature would achieve unconsciousness and insensibility.However heating to about 50° C. or more would start to produce proteindenaturation and hence permanent tissue damage.

Upon the application of the microwave energy and achievement of therequired degree of heating, the generation of microwave energy ispreferably switched off (or otherwise stopped from application to theanimal) so as to prevent further heating which would make the stunirreversible. Also the discontinuance of the application of microwaveenergy limits or prevents heating of deeper tissues, particularly thebrain stem, to any significant extent, particularly heating to causeirreversible effects. In particular, heating of the mid and deep braintissues and particularly the brain stem area (which controls cardiac andrespiratory functions) to the same extent as the frontal portion isundesirable, because it may cause immediate effects, such as heartfailure which may then lead to the stun and subsequent slaughter beingdeemed non-compliant with the religious ritual slaughter criteria, theanimal carcass being rejected as unacceptable for the intendedconsumption by the relevant religious group, with consequent devaluationof the carcass and its meat. In the case of sheep, brain stem heatingshould be limited to maintain the brain stem temperature to less thanabout 43° C.

The time period required for application of the microwave energy ispreferably as short as possible although achieving shorter times entailsgreater microwave generator power output so there is a necessarybalancing of these two parameters. However, preferably stunning toachieve the unconsciousness and insensibility in less than about 2seconds is preferred to meet reasonable animal welfare considerations(minimizing fear, anxiety, pain, suffering, and distress in the animal).Particularly preferred would be achieving the effective stun in lessthan about one second and most preferably achieving this in about 0.5seconds.

Confinement of the major heating effect to the frontal portion of theanimal brain in the process and apparatus of the invention is requiredto render the induced insensibility reversible. The frontal portion ofthe brain is involved in cognitive, perception, sensory, andconsciousness brain functioning or processes so that warming of thisportion of the brain by the extent indicated leads to unconsciousnessand insensibility but without causing irreversible damage to the braintissues and brain functioning if the elevated temperature does notexceed 50° C.

However although particularly developed and described herein in relationto reversible stunning for ritual slaughter, the apparatus and methodmay be useful for other processes requiring reversible insensibility.Examples may include veterinary procedures in which temporaryinsensibility is required or useful. To avoid the animal regainingconsciousness the microwave radiation may be applied in pulses orintermittently to maintain unconsciousness without permanent damage orother undesired effects. Analogously the apparatus and method may beuseful for other animal processes or treatments or inspections, e.g.,docking, tagging, branding, and inspections generally.

Because the stunning using the apparatus and process can produceinsensibility or unconsciousness in a manner without excessive stressand pain, the invention can be extended for use as a permanent orirreversible stunning or killing system. By increasing the power orduration of the application of microwaves, the increased heating effectand/or deeper brain heating can enable a useful alternative to currentirreversible electrical or percussive stunning of animals for slaughter.

It will be seen that the process and apparatus according to thepreferred embodiments described herein, including those described inrelation to the drawings, can enable stunning of animals, particularlyanimals for slaughter, so as to rapidly induce unconsciousness andinsensibility enabling further processing or handling, includingslaughter in a manner compliant with religious ritual criteria orhandling for temporary, such as veterinary, processes because the stunis reversible. The stun also is carried out in a way that complies withgood animal welfare handling practices. Indeed, the present inventivemethod and apparatus are potentially capable of being better thancurrent practices, particularly relating to animal welfare outcomes. Forexample success rates for rapid and reliable stunning may be better,there may be less risk of operator error, and there may be less stressto animals.

What is claimed is:
 1. An animal stunning apparatus for inducingsubstantially immediate unconsciousness and insensibility enablingprocessing or handling of a subject animal, the apparatus including: astunning station to which a live subject animal to be processed orhandled is introduced, the stunning station being arranged to locate asubject animal in a confined position, an applicator located so as tocontact an application point on the live subject animal's headimmediately overlying a frontal portion of the animal's brain, theapplicator having a coupling conformation to couple microwave radiationtherethrough to the head and to the frontal portion of the brain of thesubject animal when in the confined position at the stunning station, amicrowave generator for generating and radiating microwave energy of asuitable power level and frequency, and a waveguide coupled to thegenerator so as to receive and direct the microwave radiation to theapplicator located at an operative end of the waveguide so as to therebyheat the frontal portion of the brain of the subject animal beneath theapplication point which the applicator contacts in use, and a switchoperable so as to discontinue the application of microwave radiationeffecting heating of the frontal portion of the brain after a period oftime sufficient to have raised the temperature of the frontal portion ofthe brain of the subject animal to thereby induce the unconsciousnessand insensibility, wherein the switch is operable to discontinue theapplication of microwave radiation immediately after a period which issufficient only to rapidly induce insensibility, and insufficient (i)for the insensibility induced to be irreversible, and (ii) to causesignificant heating of deeper brain tissues and including the brainstem.
 2. The apparatus of claim 1, wherein the applicator has an openingtherein through which the microwave radiation from the waveguide iscoupled to the animal's head at the application point, the peripheralportions of the applicator defining the opening contacting the animal'shead to surround the application point when the applicator is in itsoperative position.
 3. The apparatus of claim 2, wherein the applicatorhas a coupling disk composed of microwave permeable material at theopening, the coupling disk being pressed positively against the animalhead at the application point to provide an interface for transferringpower at the application point.
 4. The apparatus of claim 1, wherein theapplicator comprises a coaxial applicator passing microwave radiationfrom the operative end of the waveguide to the application point, thecoaxial applicator having a central conductor through the length of theapplicator, the central conductor being coaxially located within asurrounding conductive sleeve thereby defining an annular microwave pathfrom the waveguide to the coupling conformation.
 5. The apparatus ofclaim 4, wherein the microwave path through the coaxial applicator isfilled with a dielectric material so as to enable higher powereddensities than air and to modify or tune the impedance.
 6. The apparatusof claim 4, wherein the coaxial applicator is connected to the operativeend of the waveguide so as to extend therefrom at an angle to thegeneral line of the waveguide, the connection between the operative endof the waveguide and the coaxial applicator being provided by atransition structure including a tapering cross-section area to providea gradual change in impedance from the waveguide and to provide matchingof the impedance between the waveguide and the coaxial applicator and tolimit or reduce reflected power losses.
 7. The apparatus of claim 1,wherein the applicator is constructed and arranged to apply themicrowaves to the animal's head so that the electric field of themicrowave energy enters the subject animal's head generallyperpendicularly to penetrate the skin and skull at the application pointand induce rapid heating of the frontal portion of the animal's brain.8. The apparatus of claim 1, wherein the generated microwave radiationcomprises a TEM type wave whereby both the electric and magnetic fieldsenter the subject animal's head generally parallel to the skin surfaceat the application point.
 9. The apparatus of claim 1, and furtherincluding an auto-tuner operatively associated with the waveguide andwhich detects the reflected power of microwave radiation in thewaveguide resulting from the degree of the impedance matching betweenthe applicator and the head and which tunes the waveguide to reduce thereflected power and increase the coupling of the microwave power to thehead.
 10. The apparatus of claim 9, wherein the auto-tuner is operatedin an iterative manner to continually tune the waveguide during theapplication of microwave radiation so as to continually improveimpedance matching while the impedance of the head changes due toheating.
 11. The apparatus of claim 1, wherein the stunning stationincludes a head positioner to locate and present to the applicator thesubject animal's head in a defined position.
 12. The apparatus of claim11, wherein the head positioner includes at least one of: a head tiltermechanism to lift the animal's head by tilting it upwardly to presentthe application point to the applicator, the head tilter comprising achin lifting member to lift the chin or lower jaw of the animal upwardlyand tilt the head backwardly to present the application point to theapplicator, a neck lifter selectively operable to raise the animal'shead (without necessarily tilting of the head) by lifting force appliedfrom beneath to the neck of the animal, thereby raising the head towardsthe applicator particularly enabling different height animals to beprocessed, and a body lifter selectively operable to raise the animal'sbody (without necessarily separately lifting or tilting of the head orlifting the neck) by lifting force applied from beneath to the body ofthe animal, thereby raising the head towards the applicator particularlyenabling different height animals to be processed.
 13. The apparatus ofclaim 1, wherein the stunning station includes a body support for thesubject animal operative to support the animal during the application ofthe microwave energy in the event that the animal starts to slump orfall at the onset of insensibility.
 14. The apparatus of claim 1,wherein the stunning station includes microwave shielding surrounding atleast the position of the animal head when the animal is in its confinedposition thereby forming a Faraday cage, the shielding having an openingfor locating the animal's head.
 15. A method of stunning an animal forinducing substantially immediate unconsciousness and insensibilityenabling processing or handling of the animal, the method comprising:introducing a live subject animal to be processed or handled to astunning station and locating the animal in a generally confinedposition, locating an applicator in contact with an application point onthe subject animal's head immediately overlying the frontal portion ofthe subject animal's brain, the applicator having a couplingconformation to couple microwave radiation through the applicator to thehead and to the frontal portion of the brain of the subject animal, andgenerating microwave radiation of a suitable power level and frequencyand directing that radiation through a waveguide to the applicator at anoperative end of the waveguide to thereby heat the frontal portion ofthe brain of the subject animal, wherein the application of themicrowave radiation to effect the heating is continued for a period oftime to raise the temperature of the frontal portion of the brain, theperiod being sufficient only to rapidly induce insensibility, andinsufficient (i) for the insensibility induced to be irreversible, and(ii) to cause significant heating of deeper brain tissues and includingthe brain stem.
 16. The method according to claim 15, wherein theapplication point is medially located on the head of the subject animalabove a line extending between the animal's eyes so as to be located atthe closest external point to the central and frontal portion of thebrain.
 17. The method according to claim 15, wherein the microwaveradiation has properties selected from: microwave radiation having itselectric field generally perpendicular to the front of the animal's headat the application point whereby the electric field enters the animal'shead in a generally perpendicular direction, and microwave radiationhaving both its electric field and magnetic field generally parallel tothe front of the animal's head at the application point and whereby themicrowave radiation enters the animal head in the generallyperpendicular direction.
 18. The method according to claim 15, whereinthe frontal portion of the brain of the subject animal is heated tosatisfy at least one of the conditions: the temperature increases by anamount in the range of about 5° C. to about 10° C., and the temperatureincreases to about 43° C.
 19. The method according to claim 15, wherein,while the animal is in the unconscious and insensible state, performingthe further step of slaughtering the animal in a manner compliant withreligious ritual slaughter criteria prescribed for Muslim “Halal”slaughter or for Judaic “Shechita” slaughter.
 20. An animal stunningapparatus for rapidly inducing unconsciousness and insensibilityenabling processing or handling of a subject animal, the apparatuscomprising: a stunning station to which a live subject animal to beprocessed or handled is introduced, the stunning station being arrangedto locate the subject animal in a confined position, the stunningstation including a head positioner to locate and present the subjectanimal's head in a defined position; an applicator located relative tothe subject animal's head when in its defined position so as to contactan application point on the live subject animal's head immediatelyoverlying a frontal portion of the animal's brain, the application pointbeing medially located on the head of the subject animal above a lineextending between the animal's eyes so as to be located at the closestexternal point to the central and frontal portion of the brain, theapplicator having a coupling conformation to couple microwave radiationtherethrough to the head and to the frontal portion of the brain of thesubject animal when in the confined position at the stunning station,the applicator having an opening therein through which the microwaveradiation from the waveguide is coupled to the animal's head at theapplication point, the peripheral portions of the applicator definingthe opening contacting the animal's head to surround the applicationpoint when the applicator is in its operative position; a microwavegenerator for generating and radiating microwave energy of a suitablepower level and frequency, and a waveguide coupled to the generator soas to receive and direct the microwave radiation to the applicatorlocated at an operative end of the waveguide so as to thereby heat thefrontal portion of the brain of the subject animal beneath theapplication point which the applicator contacts in use, stunning stationincluding microwave shielding surrounding at least the position of theanimal head when the animal is in its confined position thereby forminga Faraday cage, the shielding having an opening in which the animal'shead is located; and a switch operable so as to discontinue theapplication of microwave radiation effecting heating of the frontalportion of the brain after a period of time sufficient to have raisedthe temperature of the frontal portion of the brain of the subjectanimal to thereby induce the unconsciousness and insensibility.